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GluR3
Glutamate receptor 3 is a protein that in humans is encoded by the ''GRIA3'' gene. Function Glutamate receptors are the predominant excitatory neurotransmitter receptors in the mammalian brain and are activated in a variety of normal neurophysiologic processes. These receptors are heteromeric protein complexes with multiple subunits, each possessing transmembrane regions, and all arranged to form a ligand-gated ion channel. The classification of glutamate receptors is based on their activation by different pharmacologic agonists. This gene belongs to a family of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors. Alternative splicing at this locus results in several different isoforms which may vary in their signal transduction properties. Genome studies have uncovered a tentative link between defective GRIA3 variants and a highly elevated risk of schizophrenia. Interactions GRIA3 has been shown to interact with GRIP1 and PICK1. RNA editing Several ion ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabotropic Glutamate Receptor 3
Metabotropic glutamate receptor 3 (mGluR3) is an inhibitory Gi/G0-coupled G-protein coupled receptor (GPCR) generally localized to presynaptic sites of neurons in classical circuits. However, in higher cortical circuits in primates, mGluR3 are localized post-synaptically, where they strengthen rather than weaken synaptic connectivity. In humans, mGluR3 is encoded by the ''GRM3'' gene. Deficits in mGluR3 signaling have been linked to impaired cognition in humans, and to increased risk of schizophrenia, consistent with their expanding role in cortical evolution. Structure In humans, mGluR3 is encoded by the GRM3 gene on chromosome 7. At least five protein-coding isoforms are predicted based on genomic information. The mGluR3 protein is a seven-pass transmembrane protein. Function L-glutamate is the major excitatory neurotransmitter in the central nervous system and activates both ionotropic and metabotropic glutamate receptors. Glutamatergic neurotransmission is involved in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamate Receptor
Glutamate receptors are synaptic and non synaptic receptors located primarily on the membranes of neuronal and glial cells. Glutamate (the conjugate base of glutamic acid) is abundant in the human body, but particularly in the nervous system and especially prominent in the human brain where it is the body's most prominent neurotransmitter, the brain's main excitatory neurotransmitter, and also the precursor for GABA, the brain's main inhibitory neurotransmitter. Glutamate receptors are responsible for the glutamate-mediated postsynaptic excitation of neural cells, and are important for neural communication, memory formation, learning, and regulation. Glutamate receptors are implicated in a number of neurological conditions. Their central role in excitotoxicity and prevalence in the central nervous system has been linked or speculated to be linked to many neurodegenerative diseases, and several other conditions have been further linked to glutamate receptor gene mutations o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AMPA Receptor
The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (also known as AMPA receptor, AMPAR, or quisqualate receptor) is an ionotropic receptor, ionotropic transmembrane receptor for glutamate (iGluR) that mediates fast synapse, synaptic transmission in the central nervous system (CNS). It has been traditionally classified as a non-NMDA_receptor, NMDA-type receptor, along with the kainate receptor. Its name is derived from its ability to be activated by the artificial glutamate analog AMPA. The receptor was first named the "quisqualate receptor" by Watkins and colleagues after a naturally occurring agonist quisqualic acid, quisqualate and was only later given the label "AMPA receptor" after the selective agonist developed by Tage Honore and colleagues at the Royal Danish School of Pharmacy in Copenhagen. The ''GRIA2''-encoded AMPA receptor ligand binding core (GluA2 LBD) was the first glutamate receptor ion channel domain to be protein crystal, crystallized. Structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabotropic Glutamate Receptor 5
Metabotropic glutamate receptor 5 is an excitatory Gq-coupled G protein-coupled receptor predominantly expressed on the postsynaptic sites of neurons. In humans, it is encoded by the ''GRM5'' gene. Function The amino acid L-glutamate is the major excitatory neurotransmitter in the central nervous system and activates both ionotropic and metabotropic glutamate receptors. Glutamatergic neurotransmission is involved in most aspects of normal brain function and can be perturbed in many neuropathologic conditions. The metabotropic glutamate receptors are a family of G protein-coupled receptors, that have been divided into 3 groups on the basis of sequence homology, putative signal transduction mechanisms, and pharmacological properties. Group I includes GRM1 and GRM5 and these receptors have been shown to activate phospholipase C. Group II includes GRM2 and GRM3 while Group III includes GRM4, GRM6, GRM7, and GRM8. Group II and III receptors are linked to the inhibition of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inosine
Inosine is a nucleoside that is formed when hypoxanthine is attached to a ribose ring (also known as a ribofuranose) via a β-N9-glycosidic bond. It was discovered in 1965 in analysis of RNA transferase. Inosine is commonly found in tRNAs and is essential for proper translation of the genetic code in wobble base pairs. Knowledge of inosine metabolism has led to advances in immunotherapy in recent decades. Inosine monophosphate is oxidised by the enzyme inosine monophosphate dehydrogenase, yielding xanthosine monophosphate, a key precursor in purine metabolism. Mycophenolate mofetil is an anti-metabolite, anti-proliferative drug that acts as an inhibitor of inosine monophosphate dehydrogenase. It is used in the treatment of a variety of autoimmune diseases including granulomatosis with polyangiitis because the uptake of purine by actively dividing B cells can exceed 8 times that of normal body cells, and, therefore, this set of white cells (which cannot operate purine salvage p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine is integral to the formation of alpha-helices in secondary protein structure due to its compact form. For the same reason, it is the most abundant amino acid in collagen triple-helices. Glycine is also an inhibitory neurotransmitter – interference with its release within the spinal cord (such as during a ''Clostridium tetani'' infection) can cause spastic paralysis due to uninhibited muscle contraction. It is the only achiral proteinogenic amino acid. It can fit into hydrophilic or hydrophobic environments, due to its minimal side chain of only one hydrogen atom. History and etymology Glycine was discovered in 1820 by the French chemist He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arginine
Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) and both the amino and guanidino groups are protonated, resulting in a cation. Only the -arginine (symbol Arg or R) enantiomer is found naturally. Arg residues are common components of proteins. It is encoded by the codons CGU, CGC, CGA, CGG, AGA, and AGG. The guanidine group in arginine is the precursor for the biosynthesis of nitric oxide. Like all amino acids, it is a white, water-soluble solid. History Arginine was first isolated in 1886 from yellow lupin seedlings by the German chemist Ernst Schulze and his assistant Ernst Steiger. He named it from the Greek ''árgyros'' (ἄργυρος) meaning "silver" due to the silver-white appearance of arginine nitrate crystals. In 1897, Schulze and Ernst Winterstein (1865–1949) determined the structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Codon
The genetic code is the set of rules used by living cells to translate information encoded within genetic material ( DNA or RNA sequences of nucleotide triplets, or codons) into proteins. Translation is accomplished by the ribosome, which links proteinogenic amino acids in an order specified by messenger RNA (mRNA), using transfer RNA (tRNA) molecules to carry amino acids and to read the mRNA three nucleotides at a time. The genetic code is highly similar among all organisms and can be expressed in a simple table with 64 entries. The codons specify which amino acid will be added next during protein biosynthesis. With some exceptions, a three-nucleotide codon in a nucleic acid sequence specifies a single amino acid. The vast majority of genes are encoded with a single scheme (see the RNA codon table). That scheme is often referred to as the canonical or standard genetic code, or simply ''the'' genetic code, though variant codes (such as in mitochondria) exist. History Efforts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exon
An exon is any part of a gene that will form a part of the final mature RNA produced by that gene after introns have been removed by RNA splicing. The term ''exon'' refers to both the DNA sequence within a gene and to the corresponding sequence in RNA transcripts. In RNA splicing, introns are removed and exons are covalently joined to one another as part of generating the mature RNA. Just as the entire set of genes for a species constitutes the genome, the entire set of exons constitutes the exome. History The term ''exon'' derives from the expressed region and was coined by American biochemist Walter Gilbert in 1978: "The notion of the cistron… must be replaced by that of a transcription unit containing regions which will be lost from the mature messengerwhich I suggest we call introns (for intragenic regions)alternating with regions which will be expressedexons." This definition was originally made for protein-coding transcripts that are spliced before being translated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADARB1
Double-stranded RNA-specific editase 1 is an enzyme that in humans is encoded by the ''ADARB1'' gene. The enzyme is a member of ADAR family. Function This gene encodes the enzyme responsible for pre-mRNA editing of the glutamate receptor subunit B by site-specific deamination of adenosines. Studies in rats found that this enzyme acted on its own pre-mRNA molecules to convert an AA dinucleotide to an AI dinucleotide which resulted in a new splice site. Alternative splicing of this gene results in several transcript variants, some of which have been characterized by the presence or absence of an Alu cassette insert and a short or long C-terminal region. ADARB1 requires the small molecule inositol hexakisphosphate (IP6) for proper function. ADARB1 is an A-to-I RNA-editing enzyme that mostly acts on protein-coding substrates. See also * Adenosine deaminase Adenosine deaminase (also known as adenosine aminohydrolase, or ADA) is an enzyme () involved in purine metabolism. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
